|  | /* | 
|  | * Copyright 2011 Tilera Corporation. All Rights Reserved. | 
|  | * | 
|  | *   This program is free software; you can redistribute it and/or | 
|  | *   modify it under the terms of the GNU General Public License | 
|  | *   as published by the Free Software Foundation, version 2. | 
|  | * | 
|  | *   This program is distributed in the hope that it will be useful, but | 
|  | *   WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or | 
|  | *   NON INFRINGEMENT.  See the GNU General Public License for | 
|  | *   more details. | 
|  | * | 
|  | * TILE startup code. | 
|  | */ | 
|  |  | 
|  | #include <linux/linkage.h> | 
|  | #include <linux/init.h> | 
|  | #include <asm/page.h> | 
|  | #include <asm/pgtable.h> | 
|  | #include <asm/thread_info.h> | 
|  | #include <asm/processor.h> | 
|  | #include <asm/asm-offsets.h> | 
|  | #include <hv/hypervisor.h> | 
|  | #include <arch/chip.h> | 
|  | #include <arch/spr_def.h> | 
|  |  | 
|  | /* | 
|  | * This module contains the entry code for kernel images. It performs the | 
|  | * minimal setup needed to call the generic C routines. | 
|  | */ | 
|  |  | 
|  | __HEAD | 
|  | ENTRY(_start) | 
|  | /* Notify the hypervisor of what version of the API we want */ | 
|  | { | 
|  | movei r1, TILE_CHIP | 
|  | movei r2, TILE_CHIP_REV | 
|  | } | 
|  | { | 
|  | moveli r0, _HV_VERSION | 
|  | jal hv_init | 
|  | } | 
|  | /* Get a reasonable default ASID in r0 */ | 
|  | { | 
|  | move r0, zero | 
|  | jal hv_inquire_asid | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Install the default page table.  The relocation required to | 
|  | * statically define the table is a bit too complex, so we have | 
|  | * to plug in the pointer from the L0 to the L1 table by hand. | 
|  | * We only do this on the first cpu to boot, though, since the | 
|  | * other CPUs should see a properly-constructed page table. | 
|  | */ | 
|  | { | 
|  | v4int_l r2, zero, r0    /* ASID for hv_install_context */ | 
|  | moveli r4, hw1_last(swapper_pgprot - PAGE_OFFSET) | 
|  | } | 
|  | { | 
|  | shl16insli r4, r4, hw0(swapper_pgprot - PAGE_OFFSET) | 
|  | } | 
|  | { | 
|  | ld r1, r4               /* access_pte for hv_install_context */ | 
|  | } | 
|  | { | 
|  | moveli r0, hw1_last(.Lsv_data_pmd - PAGE_OFFSET) | 
|  | moveli r6, hw1_last(temp_data_pmd - PAGE_OFFSET) | 
|  | } | 
|  | { | 
|  | /* After initializing swapper_pgprot, HV_PTE_GLOBAL is set. */ | 
|  | bfextu r7, r1, HV_PTE_INDEX_GLOBAL, HV_PTE_INDEX_GLOBAL | 
|  | inv r4 | 
|  | } | 
|  | bnez r7, .Lno_write | 
|  | { | 
|  | shl16insli r0, r0, hw0(.Lsv_data_pmd - PAGE_OFFSET) | 
|  | shl16insli r6, r6, hw0(temp_data_pmd - PAGE_OFFSET) | 
|  | } | 
|  | { | 
|  | /* Cut off the low bits of the PT address. */ | 
|  | shrui r6, r6, HV_LOG2_PAGE_TABLE_ALIGN | 
|  | /* Start with our access pte. */ | 
|  | move r5, r1 | 
|  | } | 
|  | { | 
|  | /* Stuff the address into the page table pointer slot of the PTE. */ | 
|  | bfins r5, r6, HV_PTE_INDEX_PTFN, \ | 
|  | HV_PTE_INDEX_PTFN + HV_PTE_PTFN_BITS - 1 | 
|  | } | 
|  | { | 
|  | /* Store the L0 data PTE. */ | 
|  | st r0, r5 | 
|  | addli r6, r6, (temp_code_pmd - temp_data_pmd) >> \ | 
|  | HV_LOG2_PAGE_TABLE_ALIGN | 
|  | } | 
|  | { | 
|  | addli r0, r0, .Lsv_code_pmd - .Lsv_data_pmd | 
|  | bfins r5, r6, HV_PTE_INDEX_PTFN, \ | 
|  | HV_PTE_INDEX_PTFN + HV_PTE_PTFN_BITS - 1 | 
|  | } | 
|  | /* Store the L0 code PTE. */ | 
|  | st r0, r5 | 
|  |  | 
|  | .Lno_write: | 
|  | moveli lr, hw2_last(1f) | 
|  | { | 
|  | shl16insli lr, lr, hw1(1f) | 
|  | moveli r0, hw1_last(swapper_pg_dir - PAGE_OFFSET) | 
|  | } | 
|  | { | 
|  | shl16insli lr, lr, hw0(1f) | 
|  | shl16insli r0, r0, hw0(swapper_pg_dir - PAGE_OFFSET) | 
|  | } | 
|  | { | 
|  | move r3, zero | 
|  | j hv_install_context | 
|  | } | 
|  | 1: | 
|  |  | 
|  | /* Install the interrupt base. */ | 
|  | moveli r0, hw2_last(MEM_SV_START) | 
|  | shl16insli r0, r0, hw1(MEM_SV_START) | 
|  | shl16insli r0, r0, hw0(MEM_SV_START) | 
|  | mtspr SPR_INTERRUPT_VECTOR_BASE_K, r0 | 
|  |  | 
|  | /* | 
|  | * Get our processor number and save it away in SAVE_K_0. | 
|  | * Extract stuff from the topology structure: r4 = y, r6 = x, | 
|  | * r5 = width.  FIXME: consider whether we want to just make these | 
|  | * 64-bit values (and if so fix smp_topology write below, too). | 
|  | */ | 
|  | jal hv_inquire_topology | 
|  | { | 
|  | v4int_l r5, zero, r1    /* r5 = width */ | 
|  | shrui r4, r0, 32        /* r4 = y */ | 
|  | } | 
|  | { | 
|  | v4int_l r6, zero, r0    /* r6 = x */ | 
|  | mul_lu_lu r4, r4, r5 | 
|  | } | 
|  | { | 
|  | add r4, r4, r6          /* r4 == cpu == y*width + x */ | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_SMP | 
|  | /* | 
|  | * Load up our per-cpu offset.  When the first (master) tile | 
|  | * boots, this value is still zero, so we will load boot_pc | 
|  | * with start_kernel, and boot_sp with init_stack + THREAD_SIZE. | 
|  | * The master tile initializes the per-cpu offset array, so that | 
|  | * when subsequent (secondary) tiles boot, they will instead load | 
|  | * from their per-cpu versions of boot_sp and boot_pc. | 
|  | */ | 
|  | moveli r5, hw2_last(__per_cpu_offset) | 
|  | shl16insli r5, r5, hw1(__per_cpu_offset) | 
|  | shl16insli r5, r5, hw0(__per_cpu_offset) | 
|  | shl3add r5, r4, r5 | 
|  | ld r5, r5 | 
|  | bnez r5, 1f | 
|  |  | 
|  | /* | 
|  | * Save the width and height to the smp_topology variable | 
|  | * for later use. | 
|  | */ | 
|  | moveli r0, hw2_last(smp_topology + HV_TOPOLOGY_WIDTH_OFFSET) | 
|  | shl16insli r0, r0, hw1(smp_topology + HV_TOPOLOGY_WIDTH_OFFSET) | 
|  | shl16insli r0, r0, hw0(smp_topology + HV_TOPOLOGY_WIDTH_OFFSET) | 
|  | st r0, r1 | 
|  | 1: | 
|  | #else | 
|  | move r5, zero | 
|  | #endif | 
|  |  | 
|  | /* Load and go with the correct pc and sp. */ | 
|  | { | 
|  | moveli r1, hw2_last(boot_sp) | 
|  | moveli r0, hw2_last(boot_pc) | 
|  | } | 
|  | { | 
|  | shl16insli r1, r1, hw1(boot_sp) | 
|  | shl16insli r0, r0, hw1(boot_pc) | 
|  | } | 
|  | { | 
|  | shl16insli r1, r1, hw0(boot_sp) | 
|  | shl16insli r0, r0, hw0(boot_pc) | 
|  | } | 
|  | { | 
|  | add r1, r1, r5 | 
|  | add r0, r0, r5 | 
|  | } | 
|  | ld r0, r0 | 
|  | ld sp, r1 | 
|  | or r4, sp, r4 | 
|  | mtspr SPR_SYSTEM_SAVE_K_0, r4  /* save ksp0 + cpu */ | 
|  | addi sp, sp, -STACK_TOP_DELTA | 
|  | { | 
|  | move lr, zero   /* stop backtraces in the called function */ | 
|  | jr r0 | 
|  | } | 
|  | ENDPROC(_start) | 
|  |  | 
|  | __PAGE_ALIGNED_BSS | 
|  | .align PAGE_SIZE | 
|  | ENTRY(empty_zero_page) | 
|  | .fill PAGE_SIZE,1,0 | 
|  | END(empty_zero_page) | 
|  |  | 
|  | .macro PTE cpa, bits1 | 
|  | .quad HV_PTE_PAGE | HV_PTE_DIRTY | HV_PTE_PRESENT | HV_PTE_ACCESSED |\ | 
|  | HV_PTE_GLOBAL | (HV_PTE_MODE_CACHE_NO_L3 << HV_PTE_INDEX_MODE) |\ | 
|  | (\bits1) | (HV_CPA_TO_PFN(\cpa) << HV_PTE_INDEX_PFN) | 
|  | .endm | 
|  |  | 
|  | __PAGE_ALIGNED_DATA | 
|  | .align PAGE_SIZE | 
|  | ENTRY(swapper_pg_dir) | 
|  | .org swapper_pg_dir + HV_L0_INDEX(PAGE_OFFSET) * HV_PTE_SIZE | 
|  | .Lsv_data_pmd: | 
|  | .quad 0  /* PTE temp_data_pmd - PAGE_OFFSET, 0 */ | 
|  | .org swapper_pg_dir + HV_L0_INDEX(MEM_SV_START) * HV_PTE_SIZE | 
|  | .Lsv_code_pmd: | 
|  | .quad 0  /* PTE temp_code_pmd - PAGE_OFFSET, 0 */ | 
|  | .org swapper_pg_dir + HV_L0_SIZE | 
|  | END(swapper_pg_dir) | 
|  |  | 
|  | .align HV_PAGE_TABLE_ALIGN | 
|  | ENTRY(temp_data_pmd) | 
|  | /* | 
|  | * We fill the PAGE_OFFSET pmd with huge pages with | 
|  | * VA = PA + PAGE_OFFSET.  We remap things with more precise access | 
|  | * permissions later. | 
|  | */ | 
|  | .set addr, 0 | 
|  | .rept HV_L1_ENTRIES | 
|  | PTE addr, HV_PTE_READABLE | HV_PTE_WRITABLE | 
|  | .set addr, addr + HV_PAGE_SIZE_LARGE | 
|  | .endr | 
|  | .org temp_data_pmd + HV_L1_SIZE | 
|  | END(temp_data_pmd) | 
|  |  | 
|  | .align HV_PAGE_TABLE_ALIGN | 
|  | ENTRY(temp_code_pmd) | 
|  | /* | 
|  | * We fill the MEM_SV_START pmd with huge pages with | 
|  | * VA = PA + PAGE_OFFSET.  We remap things with more precise access | 
|  | * permissions later. | 
|  | */ | 
|  | .set addr, 0 | 
|  | .rept HV_L1_ENTRIES | 
|  | PTE addr, HV_PTE_READABLE | HV_PTE_EXECUTABLE | 
|  | .set addr, addr + HV_PAGE_SIZE_LARGE | 
|  | .endr | 
|  | .org temp_code_pmd + HV_L1_SIZE | 
|  | END(temp_code_pmd) | 
|  |  | 
|  | /* | 
|  | * Isolate swapper_pgprot to its own cache line, since each cpu | 
|  | * starting up will read it using VA-is-PA and local homing. | 
|  | * This would otherwise likely conflict with other data on the cache | 
|  | * line, once we have set its permanent home in the page tables. | 
|  | */ | 
|  | __INITDATA | 
|  | .align CHIP_L2_LINE_SIZE() | 
|  | ENTRY(swapper_pgprot) | 
|  | .quad HV_PTE_PRESENT | (HV_PTE_MODE_CACHE_NO_L3 << HV_PTE_INDEX_MODE) | 
|  | .align CHIP_L2_LINE_SIZE() | 
|  | END(swapper_pgprot) |